This invention relates generally to improvements in fluid control valves. More particularly, but not by way of limitation, this invention relates to cleaning apparatus for fluid pressure control valves. In control valves of the type described in detail hereinafter, it is desirable to reduce the pressure fluid flowing therethrough from a very high pressure to some lesser pressure and to dissipate the energy thus released in such a manner that liquids will not be vaporized nor will extremely high velocities be developed that will result in either erosion of the valve or downstream apparatus or that will result in unacceptable high noise levels as the pressure is reduced. Some examples of designs which have been proposed to accomplish the foregoing are illustrated by U.S. Pat. Nos. 3,513,864 issued May 26, 1972 to R. E. Self; 3,514,074 issued May 26, 1972 to R. E. Self; 3,529,628 issued Sept. 22, 1972 to S. A. Cummins; 3,690,344 issued Sept. 12, 1972 to Richard S. Brumm; and 4,004,613 issued Jan. 25, 1977 to Robert M. Purton and Robert B. Maddock.
Each of the foregoing describes a valve that has been designed for the purpose of reducing the pressure of fluid flowing therethrough. Each of foregoing is provided with a plurality of stacked, annular members disposed between the inlet and outlet of the valve and through which fluid must flow. Each, with the exception of U.S. Pat. No. 3,690,344, has arranged the stacked annular members in such a manner that fluid flowing through the valve must follow a very tortuous path through a plurality of orifice like openings as it passes through the valve to dissipate the energy that is released as the pressure is reduced.
In the U.S. Pat. No. 3,690,344, a plurality of stacked plates are provided, but the flow path therethrough is generally in a straight line. The energy is dissipated due to the restriction provided by the narrow spaces between the stacked plates.
Again, with the exception of the U.S. Pat. Nos. 3,690,344 and 4,004,613, it will be appreciated that the annular members that are utilized to form the flow path through the valves are of extremely complex configuration and are of such construction that the orifices can become plugged. None of the valves include built in cleanout apparatus capable of removing the cause of the plugging.
An object of this invention is to provide cleanout apparatus for an improved flow control valve having orifice plates that provide a relatively long, tortuous flow path for dissipation of the energy and at the same time, prevent flow therethrough of any particles that would be of sufficient size to block the flow path and in which the first openings into the orifice plates can be quickly and easily cleaned in place in the event they should become plugged or flow therethrough unduly restricted.
The foregoing and additional objects and advantages of the invention will be more fully understood when the following detailed description is read in conjunction with the accompanying drawing.